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Bug 865649 - app-emulation/spice-0.15.0 fails to compile (lto): spice-char.h:78:8: error: type struct SpiceCharDeviceInstance violates the C++ One Definition Rule [-Werror=odr]
Summary: app-emulation/spice-0.15.0 fails to compile (lto): spice-char.h:78:8: error: ...
Status: CONFIRMED
Alias: None
Product: Gentoo Linux
Classification: Unclassified
Component: Current packages (show other bugs)
Hardware: All Linux
: Normal normal (vote)
Assignee: Virtualization Team
URL:
Whiteboard:
Keywords:
Depends on:
Blocks: lto
  Show dependency tree
 
Reported: 2022-08-18 06:45 UTC by Agostino Sarubbo
Modified: 2022-12-18 02:35 UTC (History)
0 users

See Also:
Package list:
Runtime testing required: ---


Attachments
build.log (build.log,722.43 KB, text/plain)
2022-08-18 06:45 UTC, Agostino Sarubbo
Details

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Description Agostino Sarubbo gentoo-dev 2022-08-18 06:45:34 UTC
https://blogs.gentoo.org/ago/2020/07/04/gentoo-tinderbox/

Issue: app-emulation/spice-0.15.0 fails to compile (lto).
Discovered on: amd64 (internal ref: lto_tinderbox)

NOTE:
This machine uses lto with CFLAGS=-flto -Werror=odr -Werror=lto-type-mismatch -Werror=strict-aliasing

Here is a bit of explanation:

-Werror=lto-type-mismatch:
User to find possible runtime issues in packages. It likely means the package is unsafe to build & use with LTO.
For projects using the same identifier but with different types across different files, they must be fixed to be consistent across the codebase.

-Werror=odr:
Used to find possible runtime issues in packages. These bugs are a problem anyway but may be even worse when combined with LTO. C++ code must comply with the One Definition Rule (ODR) - see https://en.cppreference.com/w/cpp/language/definition#One_Definition_Rule.

-Werror=strict-aliasing:
Used to find possible runtime issues in packages. These bugs are a problem anyway but may be even worse when combined with LTO.

Workarounds:
- If upstream is friendly and still active, file a bug upstream. For emulators, codecs, games, or multimedia packages, it may be worth just applying a workaround instead, as upstreams sometimes aren't receptive to these bugs (VALID FOR ALL).
- Use the new 'filter-lto' from flag-o-matic.eclass as it's likely to be unsafe with LTO (VALID FOR lto-type-mismatch - odr).
- Fix it yourself if interested, of course (VALID FOR ALL).
- Append-flags -fno-strict-aliasing (VALID FOR strict-aliasing).
- Use memcpy() but a union is sometimes suitable too (VALID FOR strict-aliasing).
- -fstrict-aliasing is implied by -O2, so this must be addressed in some form (VALID FOR strict-aliasing).

See also: https://marc.info/?l=gentoo-dev&m=165639574126280&w=2
Comment 1 Agostino Sarubbo gentoo-dev 2022-08-18 06:45:37 UTC
Created attachment 800015 [details]
build.log

build log and emerge --info
Comment 2 Larry the Git Cow gentoo-dev 2022-12-18 02:35:12 UTC
The bug has been referenced in the following commit(s):

https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=4bdbf83d20cbb594e70507b64f3831d964b3e60b

commit 4bdbf83d20cbb594e70507b64f3831d964b3e60b
Author:     John Helmert III <ajak@gentoo.org>
AuthorDate: 2022-12-18 02:31:54 +0000
Commit:     John Helmert III <ajak@gentoo.org>
CommitDate: 2022-12-18 02:34:19 +0000

    app-emulation/spice: add 0.15.1
    
    Building with LTO should be fixed by [1], and the openssl-3
    issue by [2]. Both in 0.15.1.
    
    [1] https://gitlab.freedesktop.org/spice/spice/-/commit/0b86b6808a06c482ea2bdef9f24be42e0dcb74ae
    [2] https://gitlab.freedesktop.org/spice/spice/-/commit/3d32295f9e99054ae1a40d220ccef53a176c8aed
    
    Bug: https://bugs.gentoo.org/865649
    Bug: https://bugs.gentoo.org/885969
    Signed-off-by: John Helmert III <ajak@gentoo.org>

 app-emulation/spice/Manifest            |  1 +
 app-emulation/spice/spice-0.15.1.ebuild | 99 +++++++++++++++++++++++++++++++++
 2 files changed, 100 insertions(+)